Means for testing stay bolts in boilers



May 22, 1923.' 1,455,836

J. R. FLfANNERY ET AL MEQNS FOR TESTING STAY BOLTS IN BOILERS FiledSept. 11 1917 j: zm 7 B WITNESSES I W W Patented May 22, 192-3.

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JOHN Romans FLANNERY, BENJAMIN a. p. sTAFro D fA' D ETHAN i. noniis,

DELAWARE.

PITTSBURGH, PENNSYLVANIA, AssIGNoRs, BY MESNE ASSIGNMENTS, To ELAN- NERYBOLT COMPANY, or PITTSBURGH, PENNSYLVANIALA ooaPoRATIo or.

MEANS FOR TESTING STAY BoLTs .IN mums.

Application filed September 11,1917. Serial No. 190,786.

To (116 whom it may concern:

.Beit known that we, JOHN ROGERS FLAN- NERY, BENJAMIN E.. D. STAFFORD,and

' note the condition of integrity of the bolt E HAN I. 'Doons, citizensof'the United States, and residents of Pittsburgh, in the countyof'Allegheny and State of Pennsylvania, have invented certain new anduseful Improvements in Means for Testing Stay Bolts in Boilers; and wedo hereby declare the following to be a full, clear, and exactdescription of the invention, such as will "enable others skilled in theart to which it ,appertains to make and use the same.

This invention relates to improvements in means fortesting stay bolts inboilers,- the object of the invention being, to provide simple andeflicient means whereby the condition of the bolt may be determinedwithout necessity for removing anyfpo'rtion of the bolt structure.

A further object is to provide electrical means which will operate toindicate or dewhile the same is in place inthe boiler.

With these and other-objects in view, the

invention consists in certain novel features of construction andcombinations of parts as hereinafter set forth and pointed out in theclaims. I

invention, and Figure 2 is a view showing a modification.

1 represents a stay bolt for boilers and 2 one of the boiler sheets. Thebolt may be of the flexible ty e, having a rounded head 3 at one end tolib suitably mounted at one of the boiler sheets and having its otherend threaded through the other boiler sheet 2 and upset.

The bolt is provided with a tell-tale hole or bore 4 which may extendfrom one end of the bolt approximately to the other end theraeof, andterminate within the rounded hea 3.

A plug 5 of fire clay or othersuitable electrical insulating material istightly fitted in the open end of the bore 4 and carries the terminalsof a coil 6 located within said bore. This coil will preferably becomposed of naked wire of comparatively fine gauge with its convolutionselectrically spaced from each other, and said coil may contain an ironcore 7, if desired to enhance the generation of current in the circuitof the coil 6. The terminals of the coil 6 which project through theplug 5, are connected with the terminals ofa translating device 8. I

,The coil 6 is embedded within the bore 4 in a mass of material 9 whichwill, by contact of Water, cause the wire of the coil to corrode or bedestroyed and thus open the circuit of the translating device. Such willbe the result in the event the bolt should become so broken or rupturedas to admit water to the tell-tale hole. The material 9 may consist of amixture of a sulphate such respective sides of the end of the stay bolt.The coil 11 of this magnet is included in circuit with a source ofalternating electric ing itspoles applied to the boiler sheet at currentor in a circuit provided with a suitable interrupter. In the drawings,we have shown the magnet coil included in circuit with the secondary ofa transformer 12, the primary of which is connected with a suitablealternating current generator, indicated at 12.

When the magnet is applied, as above described, a current will beinduced in the coil 6 within the bore of the bolt (if the latter is notruptured) and this current will operate the translating device to denotethe good condition of the bolt. Should the bolt be broken or ruptured sothat water has been admitted into the tell-tale hole, the material 9will have so corroded the wire of the coil 6 as to open the circuit ofthe same, and hence, when the magnet is applied as above described, nocurrent will be induced in said coil and hence the translating devicewill not be operated, thus denoting that the bolt is ruptured.

In the operation of our improvements, the boiler plate will becomesaturated magnetically as will also a portion of the staybolt and asufiicient number of magnetic lines of force will cut the coil (theconvolutions of which are necessarily not parallel but at an angle tothejaath of the lines of the wall of said bore as indicated at l tand.

the other end of said coil which extends through the plu, 5, isconnected with the boiler sheet as indicated at 15. In other respects,the structure shown in Figure 2 may be the same as that shown in Figure1 Other slight changes might be made in the details of construction ofour invention without departing from the spirit thereof or limiting itsscope as defined by the appended claims andhence we do not wish torestrict ourselves to the precise details herein set forth.

Having v fully described our invention what we claim as new and desiretosecure by Letters Patent, is:

1. The combination with a stay bolt having a bore, of a coil Within saidbore, a

material'within said bore and contacting with said coil, said materialbeing such as will by contact with moisture cause severance of the wireof said coil, a translating device included in circuit with said coil,and

means for inducing an electric current in said,

coil.

ing a bore, of a coil within said bore, a translatlng device in circuitwith said 0011, an

electro -magnet, means for energizing said magnet whereby a current willbe induced in said coil when the magnet is applied to the boiler in thevicinity of the bolt, and means within the bore of the bolt forrupturing the circuit of the coil when moisture enters 'translat-ingdevice having its terminals connected with the terminals of said coil,an electro-magnet to be applied to the boiler in vicinity to the bolt, asource of alternating electric current including the coil of theelectro-magnet, and a material within the bore of the bolt which will,by contact with moisture, rupture the-circuit of said closed coil. i

In testimony whereof, we have signed this specification in the presenctof two subscrib; ing witnesses.

JOHN ROGERS FLANNERY. BENJAMIN E. D. STAFFORD. ETHAN I. DODDS WitnessesEDWIN SaRYCE, v F. H. ALLIsoN.

